On Wed, Apr 10, 2019 at 4:43 AM Ingo Molnar <mi...@kernel.org> wrote: > > > * Elena Reshetova <elena.reshet...@intel.com> wrote: > > > 2) Andy's tests, misc-tests: ./timing_test_64 10M sys_enosys > > base: 10000000 loops in 1.62224s > > = 162.22 nsec / loop > > random_offset (prandom_u32() every syscall): 10000000 loops in 1.64660s > > = 166.26 nsec / loop > > Stupid question, how did you manage to buil timing_test_64? Here it fails > with a bog standard gcc 7.3.0 x86-64 distro toolchain: > > dagon:~/luto-misc-tests.git> make timing_test_64 > g++ -m64 -o timing_test_64 -O2 -g -std=gnu++11 -pthread -Wall > timing_test.cc -lrt -ldl > /usr/bin/ld: /tmp/cc8VRkuV.o: relocation R_X86_64_32S against > `.text.startup' can not be used when making a PIE object; recompile with -fPIC > /usr/bin/ld: final link failed: Nonrepresentable section on outputcollect2: > error: ld returned 1 exit status > Makefile:39: recipe for target 'timing_test_64' failed >
I think your toolchain is screwy. If I create this file as ingo.c: #include <stdio.h> int main(int argc, char **argv) { printf("Hello world!"); return 0; } And build it like this, it fails: $ gcc -o ingo -g ingo.c -pie /usr/bin/ld: /tmp/ccofYU9N.o: relocation R_X86_64_32 against `.rodata' can not be used when making a PIE object; recompile with -fPIC /usr/bin/ld: final link failed: nonrepresentable section on output collect2: error: ld returned 1 exit status Which I assume means that -pie requires -fPIC, and your toolchain is screwed up and is defaulting to useless options. I'm guessing you should file a bug against your distro gcc package. For me, it works if I remove -pie.